Provisions on Lease for Roommate

[Paul C.]

Hi BP, 

To help out a family member I am going to rent out one side of our duplex to him, however he cannot afford the rent on his own so we are looking to find him a roommate. My question is, are there any provisions or rules that I should make in the lease on how common areas, rental payments(I want to only receive payment from one), and any disputes will be handled? I have a pretty good lease for a SFH, but this is my first with a duplex. I did a few google searches and was not really able to find any good language for my lease. Let me know if you have any ideas!